According to sporx.com, the proposal for the Brazilian is in the region of €2.5m.
Including Cetin as part of a dual deal could enable them to lower the price-tag, but they face competition from Galatasaray.
Cetin is a 23-year-old Turkey international centre-back who cost €3m to sign from Genclerbirligi last summer.
He struggled to make an impact and made just five Serie A appearances.